Tag update not fast enough

[ceilingwalker]

Hello all. I have a 5069-L306ERMS2 that is interfaced with an ABB IRC palletizing robot. I am having trouble metering cases to the pick point (controlled by PLC) when it involves a single case. What is happening is, the robot tells the PLC how many cases it requires for each pick. For cases of 2 or more, there is no issue. When it is a single case, the PLC register doesn't update fast enough and the conveyor allows an extra case through. All attempts I have made so far haven't worked because it throws a wrench into the sequencers. All of the tasks are scanned continuously, 500mS. I am thinking I should create a small routine that will update this register more predictably and quicker. What I can't decide is, should I make this event triggered (as soon as the robot sends), or periodic. I would sure appreciate some feedback on this. Thx

 

[celichi]

Hello all. I have a 5069-L306ERMS2 that is interfaced with an ABB IRC palletizing robot. I am having trouble metering cases to the pick point (controlled by PLC) when it involves a single case. What is happening is, the robot tells the PLC how many cases it requires for each pick. For cases of 2 or more, there is no issue. When it is a single case, the PLC register doesn't update fast enough and the conveyor allows an extra case through. All attempts I have made so far haven't worked because it throws a wrench into the sequencers. All of the tasks are scanned continuously, 500mS. I am thinking I should create a small routine that will update this register more predictably and quicker. What I can't decide is, should I make this event triggered (as soon as the robot sends), or periodic. I would sure appreciate some feedback on this. Thx

You could create a continuous routine, or one that is trigger based.

I have a routine that is scanned at 5ms to pick up a power failure before the VFDs go under-voltage. This happens in 1 or 2/60th of a second, so I know it can scan very fast when required.



500ms is pretty slow, maybe okay for process control.

 

[ceilingwalker]

You could create a continuous routine, or one that is trigger based.

I have a routine that is scanned at 5ms to pick up a power failure before the VFDs go under-voltage. This happens in 1 or 2/60th of a second, so I know it can scan very fast when required.

It sounds like you chose periodic and set it to 5ms?

 

[celichi]

It sounds like you chose periodic and set it to 5ms?

Yep, works great reading the Input for the 3 Phase Power Monitor before the drives Fault for Bus under voltage.

 

[ceilingwalker]

Yep, works great reading the Input for the 3 Phase Power Monitor before the drives Fault for Bus under voltage.

Thanks much!